Reporting congestion in access networks to the core network

Abstract

A network node in a core network is provided information about congestion in an access network coupled to the core network. The information about congestion includes a congestion identifier associated with a bearer that can be sent from an access node in the access network to a network node in the core network. The congestion identifier is associated with a set of bearers. The information about congestion also includes a congestion level indication sent from the access node to the network node. The network node maintains associations between the congestion identifiers and the bearers and can mitigate congestion on one or more bearers in the set of bearers associated with a congestion identifier in response to the congestion level indication.

What is claimed is: 
     
         1 . A method for an access node to report access network congestion to a network node in a core network, the method comprising:
 detecting a bearer transition event for a first bearer associated with a user equipment that is in communication with the access node;   determining a congestion identifier that is associated with a set of bearers for association with the first bearer; and   sending the congestion identifier and information identifying the first bearer to the network node.   
     
     
         2 . The method of  claim 1 , wherein the set of bearers associated with the congestion identifier are further associated with an access network cell, multiple access network cells, or an access network cell sector. 
     
     
         3 . The method of  claim 1 , wherein the set of bearers associated with the congestion identifier are further associated with a class of service. 
     
     
         4 . The method of  claim 1 , wherein the value of the congestion identifier is a cell identifier, a cell global identifier, an access node internet protocol (IP) address, an access node media access control (MAC) address, a physical cell identifier, or a random number. 
     
     
         5 . The method of  claim 1 , wherein the bearer transition event is a bearer setup or a bearer handover. 
     
     
         6 . The method of  claim 1 , wherein the bearer transition event is an attachment of the user equipment to the access network via the access node. 
     
     
         7 . The method of  claim 1 , wherein the bearer transition event is a handover of the user equipment to the access node from another access node. 
     
     
         8 . The method of  claim 1 , wherein the bearer transition event is a state transition of the user equipment from an idle state to a connected state. 
     
     
         9 . The method of  claim 1 , wherein the bearer transition event is an establishment of a new bearer associated with the user equipment. 
     
     
         10 . The method of  claim 1 , wherein the congestion identifier is dynamic. 
     
     
         11 . The method of  claim 1 , wherein the network node is a packet data network gateway, and the bearer is via a serving gateway. 
     
     
         12 . The method of  claim 1 , further comprising sending a null congestion identifier from the access node to the network node, wherein the null congestion identifier signals the network node to disassociate the bearer from a congestion identifier. 
     
     
         13 . The method of  claim 12 , wherein the null congestion identifier is sent to the network node after handover of the user equipment from the access node to another access node. 
     
     
         14 . The method of  claim 12 , wherein the null congestion identifier is sent to the network node after the user equipment enters an idle state. 
     
     
         15 . The method of  claim 1 , wherein the congestion identifier value is sent to the network node using the bearer. 
     
     
         16 . The method of  claim 1 , wherein the congestion identifier value is sent to the network node after determining that a probability of access network congestion within a time window exceeds a threshold. 
     
     
         17 . The method of  claim 16 , wherein the probability is based on at least one of an access network resource utilization, an access network scheduling queue level, or an access network scheduling queue packet aging level. 
     
     
         18 . The method of  claim 16 , wherein the probability is based on a predetermined congestion pattern. 
     
     
         19 . The method of  claim 1 , wherein the congestion identifier value is sent to the network node after detecting access network congestion. 
     
     
         20 . The method of  claim 1 , wherein a time of sending the congestion identifier to the network node is based on characteristics of the bearer. 
     
     
         21 . The method of  claim 1 , wherein a time of sending the congestion identifier to the network node is based on characteristics associated with the user equipment. 
     
     
         22 . The method of  claim 1 , further comprising
 detecting a congestion level in an access network served by the access node; and   sending a congestion level indication to the network node, wherein the congestion level indication is based on the detected congestion level.   
     
     
         23 . The method of  claim 22 , wherein the congestion level indication is sent on the bearer to the network node. 
     
     
         24 . The method of  claim 22 , wherein the bearer is one of a plurality of bearers between the access node and the network node, and wherein the congestion level indication is sent to the network node in a subset of the plurality of bearers. 
     
     
         25 . The method of  claim 22 , wherein the congestion level indication is sent in a control message to the network node. 
     
     
         26 . The method of  claim 22 , wherein the congestion level indication and the congestion identifier value are sent to the network node in a same packet. 
     
     
         27 . An access node serving a cell in an access network coupled to a core network, the access node comprising:
 a transceiver module configured to receive and send data via the access network;   a backhaul interface module configured to receive and send data via the core network;   a memory module; and   a processor module coupled to the transceiver module, the backhaul interface module, and the memory module and configured to:
 detect a bearer transition event for a first bearer associated with a user equipment that is in communication with the access node; 
 determine a congestion identifier that is associated with a set of bearers for association with the first bearer; and 
 send the congestion identifier and information identifying the first bearer from the access node to a network node. 
   
     
     
         28 . The access node of  claim 27 , wherein the set of bearers associated with the congestion identifier are further associated with an access network cell, multiple access network cells, or an access network cell sector. 
     
     
         29 . The access node of  claim 27 , wherein the set of bearers associated with the congestion identifier are further associated with a class of service. 
     
     
         30 . The access node of  claim 27 , wherein the value of the congestion identifier is a cell identifier, a cell global identifier, an access node internet protocol (IP) address, an access node media access control (MAC) address, a physical cell identifier, or a random number. 
     
     
         31 . The access node of  claim 27 , wherein the bearer transition event is a bearer setup or a bearer handover. 
     
     
         32 . The access node of  claim 27 , wherein the bearer transition event is an attachment of the user equipment to the access network via the access node. 
     
     
         33 . The access node of  claim 27 , wherein the bearer transition event is a handover of the user equipment to the access node from another access node. 
     
     
         34 . The access node of  claim 27 , wherein the bearer transition event is a state transition of the user equipment from an idle state to a connected state. 
     
     
         35 . The access node of  claim 27 , wherein the bearer transition event is an establishment of a new bearer associated with the user equipment. 
     
     
         36 . The access node of  claim 27 , wherein the congestion identifier is dynamic. 
     
     
         37 . The access node of  claim 27 , wherein the network node is a packet data network gateway, and the bearer is via a serving gateway. 
     
     
         38 . The access node of  claim 27 , wherein the processor module is further configured to send a null congestion identifier from the access node to the network node, wherein the null congestion identifier signals the network node to disassociate the bearer from a previous congestion identifier. 
     
     
         39 . The access node of  claim 38 , wherein the processor module is further configured to send the null congestion identifier from the access node to the network node after handover of the user equipment from the access node to another access node. 
     
     
         40 . The access node of  claim 38 , wherein the processor module is further configured to send the null congestion identifier from the access node to the network node after the user equipment enters an idle state. 
     
     
         41 . The access node of  claim 27 , wherein the congestion identifier value is sent to the network node using the bearer. 
     
     
         42 . The access node of  claim 27 , wherein the congestion identifier value is sent to the network node after determining that a probability of access network congestion within a time window exceeds a threshold. 
     
     
         43 . The access node of  claim 42 , wherein the probability is based on at least one of an access network resource utilization, an access network scheduling queue level, or an access network scheduling queue packet aging level. 
     
     
         44 . The access node of  claim 42 , wherein the probability is based on a predetermined congestion pattern. 
     
     
         45 . The access node of  claim 27 , wherein the congestion identifier value is sent to the network node after detecting access network congestion. 
     
     
         46 . The access node of  claim 27 , wherein a time of sending the congestion identifier value to the network node is based on characteristics of the bearer. 
     
     
         47 . The access node of  claim 27 , wherein a time of sending the congestion identifier value to the network node is based on characteristics associated with the user equipment. 
     
     
         48 . The access node of  claim 27 , wherein the processor module is further configured to:
 detect a congestion level in an access network served by the access node; and   send a congestion level indication to the network node, wherein the congestion level indication is based on the detected congestion level.   
     
     
         49 . The access node of  claim 48 , wherein the congestion level indication is sent on the bearer to the network node. 
     
     
         50 . The access node of  claim 48 , wherein the bearer is one of a plurality of bearers between the access node and the network node, and wherein the congestion level indication is sent to the network node in a subset of the plurality of bearers. 
     
     
         51 . The access node of  claim 48 , wherein the congestion level indication is sent in a control message to the network node. 
     
     
         52 . The access node of  claim 48 , wherein the congestion level indication and the congestion identifier value are sent to the network node in a same packet. 
     
     
         53 . A method for a network node in a core network to manage congestion in an access network coupled to the core network, the method comprising:
 receiving a congestion identifier and information identifying a first bearer;   associating the congestion identifier with the first bearer based on the information identifying the first bearer;   receiving a congestion level indication; and   associating the congestion level indication with the congestion identifier.   
     
     
         54 . The method of  claim 53 , wherein the method further includes mitigating congestion on the first bearer. 
     
     
         55 . The method of  claim 53 , wherein the congestion identifier is a cell identifier, a cell global identifier, an access node internet protocol (IP) address, an access node media access control (MAC) address, a physical cell identifier, or a random number. 
     
     
         56 . The method of  claim 53 , further comprising sending an identifier of the network node in response to receiving the congestion identifier. 
     
     
         57 . The method of  claim 53 , further comprising:
 receiving a null congestion identifier for the first bearer; and   disassociating the first bearer from a previous congestion identifier.   
     
     
         58 . The method of  claim 53 , wherein the congestion identifier is received on one of a plurality of bearers, and wherein associating the congestion identifier with the first bearer is based on the one of the plurality of bearers on which the congestion identifier value is received. 
     
     
         59 . The method of  claim 53 , wherein the congestion level indication is received on one of a plurality of bearers, and wherein associating the congestion level indication with the congestion identifier comprises:
 determining the congestion identifier associated with the one of the plurality of bearers on which the congestion identifier is received; and   determining the one or more of the plurality of bearers connected to the network node that are associated with the congestion identifier value associated with the one of the plurality of bearers on which the congestion identifier is received.   
     
     
         60 . A network node in a core network coupled to an access network, the network node comprising:
 an input/output module configured to communicate with an access node in the access network;   a memory module; and   a processor module coupled to the input/output module and the memory module and configured to:
 receive, from the access node, a congestion identifier and information identifying a first bearer; 
 associate the congestion identifier with the first bearer based on the information identifying the first bearer; 
 receive, from the access node, a congestion level indication; and 
 associate the congestion level indication with the congestion identifier. 
   
     
     
         61 . The network node of  claim 60 , wherein the processor module is further configured to mitigate congestion on the first bearer. 
     
     
         62 . The network node of  claim 60 , wherein the congestion identifier is a cell identifier, a cell global identifier, an access node internet protocol (IP) address, an access node media access control (MAC) address, a physical cell identifier, or a random number. 
     
     
         63 . The network node of  claim 60 , wherein comprising send an identifier of the network node to the access node in response to receiving the congestion identifier. 
     
     
         64 . The network node of  claim 60 , wherein the processor module is further configured to:
 receive a null congestion identifier for the first bearer; and   disassociate the first bearer from a previous congestion identifier.   
     
     
         65 . The network node of  claim 60 , wherein the congestion identifier is received on one of a plurality of bearers, and wherein the processor module is further configured to associate the congestion identifier with the first bearer based on the one of the plurality of bearers on which the congestion identifier is received. 
     
     
         66 . The network node of  claim 60 , wherein the congestion level indication is received on one of a plurality of bearers, and wherein the processor module is further configured to associate the congestion level indication with the first bearer by:
 determining the congestion identifier associated with the one of the plurality of bearers on which the congestion identifier is received; and   determining the one or more of the plurality of bearers connected to the network node that are associated with the congestion identifier value associated with the one of the plurality of bearers on which the congestion identifier is received.